Definition
A rotorcraft that derives both its lift and its propulsion from one or more power-driven rotors mounted on substantially vertical axes. The rotor blades themselves act as rotating wings, allowing the aircraft to take off and land vertically, hover in place, and fly forward, backward, or sideways.
Plain English
An aircraft that flies using spinning blades on top instead of fixed wings. Because the blades produce both the lift and the thrust, it can rise straight up, hold still in the air, and move in any direction.
Context Anchor
You will see this term in general aircraft descriptions, air traffic instructions, airport procedures, and rules that apply differently to helicopters than to airplanes.
Derivation
From the French 'hélicoptère', combining the Greek 'helix' (spiral) and 'pteron' (wing). Literally 'spiral wing' — a fitting description of how the rotating blades carve through the air to produce lift.
Why Pilots Care
Helicopters operate under different rules and traffic patterns than fixed-wing aircraft. Knowing what qualifies as a helicopter matters when reading airspace rules, approach procedures, and right-of-way regulations, since many sections of the AIM apply specifically to them.
Intuition Check
Do not think of a helicopter as simply an airplane with blades on top. Its rotating blades provide the main lift, which is why it can hover and lift off without a runway.
Example Sentence 1
The helicopter hovered briefly over the pad before setting down gently on the rooftop.
Example Sentence 2
Helicopters allow access to remote sites where airplanes cannot land due to lack of runway space.